This invention relates to rotary boring tools for use in boring operations and, more particularly, to tools in which a boring bar is provided with a generally radially disposed tool holder adjustable generally radially of the boring bar.
Adjustable tool holders have generally required complicated machining operations in the boring bars in which they have been received. Keyways, chamfers and bores of varying diameter have generally been required to receive the tool holder and permit the same to be adjusted in axial dimension to the required fine tolerance. Correspondingly, the adjustable tool holders themselves have been complex, requiring complex assembly procedures to install them in the boring bar.
Accordingly, it is a principal object of the present invention to provide an adjustable tool holder for a boring bar that will only require the drilling and reaming of one constant diameter cylindrical bore in the boring bar.
It is a further object of the present invention to provide an adjustable tool holder comprising a unitary structure after assembly, thereby easily to be inserted and received in the boring bar.
It is a still further object of the present invention to provide an adjustable tool holder of the type described that will be of constant outer dimension along its entire length.
It is a still further object of the present invention to provide an adjustable tool holder of the type described including a shank comprising two mating parts, the two parts being keyed together to prevent relative rotation therebetween without the necessity of any keying means in the boring bar itself.